Method of and machine for folding sheet material



March 2, 1937. c, MacDONALD METHOD OF AND MACHINE FOR FOLDING SHEET MATERIAL Filed Dec. 24, 1952 Tag Ill 2 32 Patented Mar. 2, 1937 UNITED STATES METHOD OF AND MACHINE FOR FOLDING SHEET MATERIAL Clifford K. MacDonald, Brockton, Mass., assignor to United Shoe Machinery Corporation, Paterson, N. J a corporation of New Jersey Application December 24, 1932, Serial No. 648,807

11 Claims.

edges thereon. Two procedures are in common use. In the first, the margin of the shoe part is skived, a coating of cement is applied to the margin, and then the margin is folded. In the other procedure, a narrow binding strip, usually of fabric, is sewed along the edge of the shoe part, cement is applied to the strip, and then the free portion of the strip is folded about the edge of the shoe part. Thus in both cases, the cement-coated margin of a piece of sheet material is folded over upon the body portion thereof. It has been proposed to apply cement to the skived margins of shoeparts during the folding operation, but such proposals have .includedeither the application of the cement at a distance from the locality inwhich the folding is taking place or the intermittent application of cement; and neither of these proposed procedures has been successful so far as I am, aware, a

In one aspect, the present invention relates to a method of progressively folding the margin of a piece of sheet material over upon the body portion and pressing the margin into place, and continually applying a ribbon of cement restricted to the body of the work in a locality adjacent to that in which thefolding is taking place. Preferably, a thick viscousgcement in the form of a ribbon is applied to the bodyportion of the work, said cement being of such consistency that it is' tacky when applied so that the margin folded over upon is continuallyforced through apassageway formed work. Any suitable cement may be used but, pref erably, a cement of the cold type will be employed which is so thick that it may be forced through a suitably shaped nozzle and directed upon the work in the form of a sticky ribbon.

In another aspect, the invention relates to a machine by the use of which the method may be practiced. In the illustrated machine the cement is continually forced through a passageway formed in thepresser foot of a folding machine which foot engages the work close to the line of the fold.

Referring to the accompanying drawing,

Fig. l is a front elevation of a portion of a machine bywhich the method maybe conveniently practiced, said machine being of that type which is particularly adapted to fold a binding strip about the edge of a piece of sheet material; and

Fig. 2 is a detail showing on an enlarged scale a piece of work in process of being operated upon. I

The illustrated folding machine comprises a 5' work support l! located at the outer end of an arm l3 which extends horizontally above the bench upon which the machine is mounted. Extending horizontally over the arm 53 is an overhanging arm l5; and the work-engaging parts of lo the machine are carried by these two arms. These Work-engaging parts comprise an edge guide l! which engages the edge of the leather or other sheet material, a combined presser foot and fold guide l between which and an intermittently- 1 5" operated block 2! the work is fed intermittently, a folder 23 which reciprocates in an inclined path from a position below the level of the work to a position above it to bend the margin of the work about the edge of the leather and about the edge of the presser foot It so as to form the fold, and a cooperating hammer 25 and anvil 2'! which act both to press the fold and to feed the work. The anvil moves to and fro substantially in the direction of feed movement. four-motion work-feeding 'movement. It descends upon the upwardly-bent margin of the work, when the anvil is close to the folder 23, as shown in Fig. 2, so as to press the fold and grip the work; then the hammer and anvil move together away from the folder 23 to feed the Work one step, whereupon the hammer rises, and the hammer and anvil return to initial positions to go through the same cycle again. In order to hold the work stationary during the pauses in the intermittent feed movements, at which times the folder 23 operates, the block 2! is fast to a small horizontal shaft (not shown) which is rocked intermittently in proper timed relation to the movements of the hammer and the anvil. When this block is rocked upwardly, the work is gripped firmly between it and the presser foot l9, which has a thin edge about which the folder 23, when it rises, bends the margin of the work. The

guide I1 is carried at one end of a lever 3i pivoted about a stud 33 carried by a bracket which is fast to the overhanging arm l5, the other end of the lever having a finger-piece by which the lever may be depressed against the force of a tension spring ill when it is desired to raise the guide ll. Also pivoted about the stud 33is a carrier 39 in the outer end of which the presser foot or fold guide i9 is slidably mounted. A spring, not shown, continually urges the presser foot 19 downward in its sliding bearing in the car- The hammer 25 has a Q5 rier 39 as far as a set-screw 4| will permit. The carrier 39 is held yieldingly in the angular position shown about the axis of the stud 33 by a spring, not shown, and may be swung clockwise about this stud at any time by depressing a fingerpiece 53 whenever, for any reason, it is desired to lift the presser foot l9. The carrier 39 is also pivotally connected at 45 to the .outer end of a horizontal rod ll which may be moved by a treadle, not shown, to raise the presser foot I9. The mechanisms for operating the anvil 21, the hammer 25, the folder 23 and the block 2! are or may be the same as the corresponding mechanisms of the machine shown in Letters Patent of the United States No. 1,702,598, granted February 19, 1929, upon an application filed in the name of Perley R. Glass, to which reference is made for a detailed description. No further description of the machine, except the cement-applying mechanism, will be given since the details of its construction, as thus far described, form no part of the present invention which, as will presently appear, may be embodied in any suitable machine by the use of which the margin of a piece of flexible sheet material may be progressively folded. It will be noted, however, that the work is fed away from the observer, as viewed in the figures, and that the margin of the Work is progressively folded and pressed.

The particular piece of Work shown is of the type known as French binding. It consists of a piece of flexible material Hi9, such as leather, to one edge of which an edge of a fabric binding strip 295 has been sewed. In the operation of the machine the free portion of this strip is folded about the edge of the leather and pressed firmly into place. In order to cause the binding to adhere to the leather or other piece of sheet material, a stripe of cement-herein shown as a ribbon of thick sticky cement the base of which is latexis applied to the leather in the locality in which the folding is taking place through a passageway in the presser foot l9. Although the cement shown is of the latex type, any suitable cement which is sticky when applied and does not require drying to make it sticky may be used.

The upright stem of the presser foot I9 is provided with a chamber 49 from the lower portion of which leads a passageway 5 I. This chamber is closed at the top by a small plate 53 through a hole in which extends the upper end of the vertical stem 55 of a force feed member 51 in the form of a screw, said member being located in the reduced lower portion of the chamber 59. The upper end of the stem 55 is of enlarged diameter and has fast to it a pulley 59 which is continually rotated by means of a belt 6|, said belt passing over guide pulleys, one of which is shown at 63, and around the hub of a hand wheel 65 which is fast to the driving shaft 5? of the machine. The stem 55 of the force feed member 51 is held from upward movement by engagement of the upper face of a collar 56 formed on the stem 55 with the lower face of a downwardly projecting hollow lug formed on the under side of the plate 53. Downward movement of the stem 55 is prevented by engagement of a downwardly extending lug on the pulley 59 with the top of the plate 53, said plate being fastened to the top of the hollow stem of the presser foot 19 by cap screws, one of which is shown at 58. Thus, when the belt has been removed from the pulley and the cap screws 58 have been removed, the pulley, the plate and the force feed member may be removed as a unit. A receptacle or reservoir 69 for cement is carried by the stem of the presser foot l9 and has an opening in its side near its bottom which connects with an opening H leading into the chamber 49 in the stem of the presser foot.

In the operation of the machine the work is fed intermittently away from the observer by the combined action of the fold presser or hammer 25 and the anvil 21. As the work passes progressively through the machine, being guided by the edge guide H, the fold is first formed by the upward movement of the folder 23 which bends the binding strip about the edge of the leather, the leather being at that time engaged close to its edge by the presser foot l9 and thus held from rising. As the work moves along, a ribbon of thick sticky cement is forced through the passageway 5|, which is in effect a nozzle, and is delivered upon the margin of the leather at the locality in which the folding is taking place. Immediately after the fold has been formed by bending up a portion of the strip 209, the fold presser 25 engages the bent-up portion, lays it down and presses it upon the ribbon or stripe of cement. The fold presser and anvil then move to feed the work. It will be noted that the speed of rotation of the force feed member 51 varies with the speed of the driving shaft 61 and that consequently the rate of delivery of cement is proportional to the rate at which the work is being fed. By properly proportioning the size of the pulley 59 to that of the hub of the hand wheel 65, a proper amount of cement may be delivered to the work irrespective of the rate of feed of the work.

Although a particular kind of work has been shown in which the margin consists of a binding strip, it should be understood that the invention in its broader aspects is not limited to this particular sort of work; and, although a particular machine has been shown and described, it should be understood that in so far as the invention is concerned with a machine, it is not limited to any particular type of folding machine.

Having described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. That improvement in folding the margin of a piece of sheet material which comprises progressively folding the margin thereof over upon the body portion, pressing said margin into place, and continuously flowing upon the work in the locality of the fold line, prior to the pressing operation, a ribbon of thick cement.

2. That improvement in folding about the edge of a piece of sheet material the free portion of a binding strip, one edge of which is attached to the edge of the sheet material, which comprises progressively directing upon the margin only of the sheet material a ribbon of cement, and progressively folding the free portion of the strip about the edge of the sheet material and pressing it upon said stripe.

3. That improvement in folding about the edge of a piece of sheet material the free portion of a binding strip, one edge of which is attached to the edge of the sheet material, which comprises progressively forming a ribbon of thick viscous cement, progressively applying the ribbon to the margin of the sheet material, and progressively folding the free portion of the strip about the edge of the sheet material and pressing it upon the ribbon of cement.

4. That improvement in folding about the edge of a piece of sheet material the free portion of a binding strip, one edge of which is attached to the edge of the sheet material, which comprisesprogressively forming a ribbon of thick viscous cement, progressively applying the ribbon to the margin of the sheet material and restricting the application of cement to the sheet material, and progressively folding the free portion of the strip about the edge of the sheet material and pressing it upon the ribbon of cement.

5. A machine of the class described having, in combination, means for feeding a piece of work forwardly, for forming a fold in the margin thereof during said forward movement and for pressing the fold, and means for continuously flowing a stream of thick, tacky cement upon the Work in a locality to underlie the folded margin during said forward movement.

6. A machine of the class described having, in combination, means for feeding a piece of work, for forming a fold in the margin thereof and for pressing the fold, said means including presser foot which engages one face of the work, and means for delivering cement through the presser foot to the work.

7. A machine of the class described having, in combination, means for feeding a piece of work, for forming a fold in the margin thereof and for pressing the fold, a chamber for cement, and means for forcing cement from the chamber and for delivering it upon the work in a, ribbon parallel to the margin to be folded prior to the pressing operation.

8. A machine of the class described having, in combination, means for feeding a piece of work, for forming a fold in the margin thereof and for pressing the fold, force feed mechanism for delivering cement to the work prior to the pressing of the fold, and means for varying the rate of delivery of the cement in accordance with the rate of feed of the work.

9. A machine of the class described having, in

combination, means for feeding a piece of work, a presser foot, a folder, a fold presser, and force feed mechanism associated with the presser foot for delivering cement to the work prior to the operation of the fold presser.

10. A machine for operating upon a piece of work which consists of a piece of sheet material to which a strip of binding has been attached having, in combination, means for progressively feeding the work for forming a fold in the binding and for pressing the fold, a chamber containing cement, and force feed screw mechanism for positively expelling cement from the chamber and directing it upon the margin of the sheet material prior to the pressing operation.

\ 11. A machine for operating upon a piece of Work which consists of a piece of sheet material to which a strip of binding has been attached having, in combination, means for progressively feeding the Work for forming a fold in the binding and for pressing the fold, a chamber containing cement, and force feed screw mechanism located in the chamber for expelling cement from the chamber and directing it upon the margin of the sheet material prior to the pressing operati-on.

CLIFFORD K. MACDONALD.

CERTIFICATE OF CORRECTION.

Patent NO. 2,072,211. March 2, 1.937.

CLIFFORD K. MaoDONALD.

It. is hereby certified that error appears in the printed Specification of the above numbered patent requiring correction as follows: Page 1, first column, line 57, strike out the words "is continually forced through a passageway formed" and. insert instead it will firmly adhere to the body portion of the; and that the said Letters Patent should be read. with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 30th day oi March, A. D. 1937.

Henry Van Arsdale (Seal) Acting Commissioner of Patents. 

